Amortization

Etymology

From Old French amortir, "to deaden, kill off," from Vulgar Latin admortire, built on Latin mors, mortem, "death" (ad-, "to," plus mors). To amortize a debt is literally to "kill it off" bit by bit until it is gone.

noun · /am-or-tih-ZAY-shun/
Paying off a debt gradually through scheduled installments, or spreading the cost of an intangible asset across the years it is used.
What it names
It shows why early mortgage payments are mostly interest: an amortization schedule front-loads the cost of borrowing before it starts eating into what you actually owe.
Example
Over a thirty-year amortization, most of the first decade’s payments went straight to interest.
Related idea
Depreciation deadens the value of physical things; amortization does the same for loans and intangible assets.